Active Fermentation: Pasteurization vs. Sterile Filtration to remain residual sugar.

[Jannis Wegmann]

Hello everybody!

My goal is to make a carbonated cider with a little residual sugar. (I think I will aim for around 5%ABV and a SG of ~1.010).

I'm interested in a way to achieve this goal without back-sweetening as I think it's appealing not to have any added sugar in my cider but rather have the little sweetnes come from the apples alone.

So far so good. I'm fairly new to cider making but I am rather ambitious since my first two batches of cider turned out pretty nicely already with the "easy" ferment-it-to-dry-and-backsweeten-method.

I've done some research on this topic and as it seems there are two (three with keeving) possible ways of doing this.

Number one: Pasteurization - kill the yeast with heat.

So I know this is usually done after fermentation to dryness, in the bottle, after the yeast served for carbonation with priming sugar.

Is it also possible to pasteurize the whole batch of cider while it is still at a SG of around 1.010? So while the fermentation is still ongoing?

If so, you could just rack the Cider off the dead yeast, (if needed use some fining agents), force-carbonate it and counter-pressure-bottle.

I'm a bit hesitant when it comes to pasteurizing though, because I don't want the heat to change the flavor-profile... Caramelly and pie-y is not what I'm looking for.

Number two: Cold-crash and filtration

This is the method that sounds really really good to me in theory and I'm wondering a bit that you don't seem to hear about it more often.

When the desired SG is reached, I would cold crash the batch at around -1°C for a week to let the yeast floccutate, then rack off the lees. (On my first batches I used M02 Cider Yeast, for easier cold crashing and a slower fermentation, CEG [Epernay II] might be more suitable)

Afterwards the cider would need to be sterile filtrated, before force-carbing and bottling.

I know that one flaw of this second method is the price of the equipment to do this on a larger scale. Cross-flow-filtration-devices are costly and the chilling requires equipment as well - but once you have those things, the variable cost shouldn't be that high.

I'm thinking of trying the second method on a small scale, to see how it turns out.

I can cool a 12 Liter tank in the refrigerator to a low enough temperature and sterile filtration can be done with a simplex-filter.

I'm really interested on any Input of you more experienced cider-makers out there! Currently I'm still developing methods on a small scale to produce the great cider I have in mind - and then go for a larger scale once harvest arrives this autumn.

Please let me know what you think of my thoughts on this so far - I would really appreciate it!

Thanks in advance,

Jannis

[Dougal]

Hi there

We cold crash and cross flow filter to retain 6-12gms residual sugar.  The ciders are also sterile filtered as they go through the carbonation unit en route to bottling.

I think that you are really starting to work to get natural sugars only above 15gm/L and get everything to stop nicely.